Commit 7981593b authored by Joe Perches's avatar Joe Perches Committed by Greg Kroah-Hartman
Browse files

mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit 



Convert the unbound sprintf in hugetlb_report_node_meminfo to use
sysfs_emit_at so that no possible overrun of a PAGE_SIZE buf can occur.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Acked-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Link: https://lore.kernel.org/r/894b351b82da6013cde7f36ff4b5493cd0ec30d0.1600285923.git.joe@perches.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 948b3edb

drivers/base/node.c

+1 −1
Original line number Diff line number Diff line
@@ -473,7 +473,7 @@ static ssize_t node_read_meminfo(struct device *dev, 
				    HPAGE_PMD_NR)

#endif

			    );

	len += hugetlb_report_node_meminfo(nid, buf + len);

	len += hugetlb_report_node_meminfo(buf, len, nid);

	return len;

}

include/linux/hugetlb.h

+2 −2
Original line number Diff line number Diff line
@@ -129,7 +129,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 
				unsigned long start, unsigned long end,

				struct page *ref_page);

void hugetlb_report_meminfo(struct seq_file *);

int hugetlb_report_node_meminfo(int, char *);

int hugetlb_report_node_meminfo(char *buf, int len, int nid);

void hugetlb_show_meminfo(void);

unsigned long hugetlb_total_pages(void);

vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -245,7 +245,7 @@ static inline void hugetlb_report_meminfo(struct seq_file *m) 
{

}



static inline int hugetlb_report_node_meminfo(int nid, char *buf)

static inline int hugetlb_report_node_meminfo(char *buf, int len, int nid)

{

	return 0;

}

mm/hugetlb.c

+10 −8
Original line number Diff line number Diff line
@@ -3582,12 +3582,14 @@ void hugetlb_report_meminfo(struct seq_file *m) 
	seq_printf(m, "Hugetlb:        %8lu kB\n", total / 1024);

}



int hugetlb_report_node_meminfo(int nid, char *buf)

int hugetlb_report_node_meminfo(char *buf, int len, int nid)

{

	struct hstate *h = &default_hstate;



	if (!hugepages_supported())

		return 0;

	return sprintf(buf,



	return sysfs_emit_at(buf, len,

			     "Node %d HugePages_Total: %5u\n"

			     "Node %d HugePages_Free:  %5u\n"

			     "Node %d HugePages_Surp:  %5u\n",

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